Elastic hot melt adhesive  composition and an elastic composite made with the same

ABSTRACT

This invention claims hot melt adhesive compositions that can be used to form elastic composites that are useful in disposable absorbent articles. The compositions have good elastic recovery and high peel adhesion at a viscosity of less than about 15,000 cps at 177° C. (350° F.). The low viscosity makes it possible to apply the hot melt adhesive at a high line speed and target application to only those areas requiring elastic performance.

This application claims priority to and benefit of provisional filedpatent application Nos. 62/048047 and 62/048066 filed on Sep. 9, 2014and provisional patent application No. 62/171129 filed on Jun. 4, 2015.

BACKGROUND

Adhesives are often used to bond substrates together. In the area ofindustrial adhesives, hot melt adhesives are commonly used to bondtogether a wide variety of articles including disposable absorbentarticles comprising non-woven substrates e.g. diapers, training paints,surgical garments, swim wear, absorbent underpants, adult incontinenceproducts, sanitary napkins and medical dressings (e.g. wound careproducts).

There can be multiple hot melt adhesives used in the manufacture of adisposable absorbent article. For example, in the manufacture of adisposable diaper, hot melt adhesives are used for construction (e.g.bonding the backsheet to the nonwoven and optionally the absorbent pad),elastic attachment (e.g. bonding the elastic material to the backsheetin for example the leg or waist area), and for the core stabilization(e.g. applying a hot melt adhesive to the absorbent core to increase thestrength of the core).

Hot melt adhesives can also be used to form elastic composites that areuseful in disposable articles. Currently, elastic composites are oftenformed in a 5-layer configuration including the following layers:nonwoven, hot melt adhesive, elastic material, hot melt adhesive,nonwoven. The hot melt adhesive bonds the non-adhesive elastic to thenonwoven to form a composite.

Alternately, a hot melt adhesive with elastic properties can replaceboth the elastic material and the adhesive layers to form a simplified3-layer elastic composite that can impart stretch to various portions ofthe disposable article.

SUMMARY

In one embodiment, the invention includes an elastic composite includinga first and second substrate; and a hot melt adhesive compositionbetween the first and second substrates thereby permanently bonding thefirst and second substrates to each other and providing elasticity inthe bonded area, said hot melt adhesive composition including about 35%by weight to about 60% by weight of one or more styrene blockcopolymers, wherein the one or more styrene block copolymers has anaverage styrene content of at least about 30% by weight and an averageMFR (200° C./5 kg) of no less than about 20, greater than about 15% of aplasticizer and, a tackifying agent; wherein the hot melt adhesivecomposition has a viscosity of less than about 15,000 cps at 350° F.

In one aspect, the elastic composite includes a hot melt adhesivecomposition with a viscosity of less than about 10,000 cps at 350° F. Inanother aspect, the one or more styrene block copolymers have an averagestyrene content of at least about 35% by weight. In a different aspect,the elastic composite includes a hot melt adhesive composition includesfrom about 25% by weight to about 40% by weight tackifying agent.

In another aspect, the elastic composite includes a hot melt adhesivecomposition comprises at least one tackifying agent with a melt point ofless than 100° C.

In one aspect, elastic composite includes a first and second substratethat are nonwoven. In a different aspect, the nonwoven is airlaid,carded and hydroentangled. In another aspect, the nonwoven is extensibleto greater than 100% in the cross web direction.

In one aspect, the hot melt adhesive of the elastic composite is appliedto the substrate using an applicator method selected from the groupconsisting of slot and non contact coating. In a different aspect, thehot melt adhesive is applied to the substrate using an applicator methodselected from the group consisting of screen printing, spraying, combshim slot and gravure roll.

In another embodiment, includes a disposable article that includes theelastic composite. In one aspect, the elastic composite is used in anapplication selected from the group consisting of ear, waist band, bellyband and side panel. In another aspect, the disposable article isselected from the group consisting of diaper, adult incontenenceproduct, feminine hygiene product and medical bandage.

In one aspect, the invention includes a hot melt adhesive compositionthat can be used to create a bonded, elasticized region, including fromabout 35% to about 60% by weight of one or more styrene block copolymerswherein the one or more styrene block copolymers has an average styrenecontent of at least about 35% and an average MFR (200° C./5 kg) of noless than about 20, greater than about 15% plasticizing oil and, atackifying agent where the adhesive composition has a viscosity of lessthan about 15,000 cps at 350° F.

In one embodiment, the hot melt adhesive composition has a ViscosityRatio (Viscosity @ 300° F. (cps)/Viscosity @ 3 350° F.) of no greaterthan about 5. In another embodiment, the tackifying agent is ahydrocarbon resin with about 5% to about 20% by weight of aromaticcontent and the plasticizing oil is a naphthertic oil.

In another aspect, the invention includes a hot melt adhesivecomposition that can be used to create a bonded, elasticized region,including from about 40% to about 55% by weight of one or more styreneblock copolymers wherein the one or more styrene block copolymers has anaverage styrene content of at least about 35% and an average MER (200°C./5 kg) of no less than about 20, from about 15% to about 30% of anaphthenic plasticizing oil and, from about 30% to about 40% by weightof an aromatic modified hydrocarbon resin where the adhesive compositionhas a viscosity of less than about 15,000 cps at 350° F.

In one embodiment, at least one of the styrene block copolymers has adiblock content of greater than about 30% by weight. In anotherembodiment, the average styrene content of the one or more styrene blockcopolymers is at least about 40% by weight. In still another embodiment,the one or more styrene block copolymers has an average MFR (200° C./5kg) of no less than about 30.

In another aspect, the elastic composite includes a substrate, and a hotmelt adhesive composition that can be used to create a bonded,elasticized region, including from about 35% to about 60% by weight ofone or more styrene block copolymers wherein the one or more styreneblock copolymers has an average styrene content of at least about 35%and an average MFR (200° C./5 kg) of no less than about 20, greater thanabout 15% plasticizing oil and, a tackifying agent where the adhesivecomposition has a viscosity of less than about 15,000 cps at 350° F. andwherein the hot melt adhesive provides elasticity to the bonded area.

DETAILED DESCRIPTION

Applicants have discovered hot melt adhesive compositions that can beused to form elastic composites that are useful in disposable articles(e.g. disposable absorbent articles). The compositions have good elasticrecovery and high peel adhesion and have a viscosity of less than about15,000 cps at 350° F. The low viscosity makes it possible to apply thehot melt adhesive at a high line speed and register i.e. provide zonedapplication to only those areas requiring elastic performance. The lowviscosity further makes it possible to apply the hot melt adhesivewithin the disposable article manufacturing line.

Elastic Composite

The elastic composite can include a first substrate and a hot meltadhesive composition. The hot melt adhesive composition impartselasticity to the first substrate.

Alternately, the elastic composite can include a first substrate, asecond substrate and a hot melt adhesive composition. The hot meltadhesive composition is present between the first and second substrate,permanently bonding the substrates to each other and providingelasticity in the bonded area.

At least one of the substrates is selected from the group consisting ofnonwoven and polymer film.

Any nonwoven can be used. The nonwoven can be an elastic nonwoven (e.g.core and shell type). The nonwoven can contain fibers made from one ormore polymers (e.g. PET (polyethylene terephthalate), PBT (polybutyleneterphthalate), nylon, polypropylene and polyethylene), one or morenatural fibers (e.g. rayon cellulose, cotton cellulose, hemp andviscose) or combinations thereof. The nonwoven can be formed by a numberof different methods, including e.g. airlaid, wetlaid, spunbound ormeltblown. The fibers can be carded (e.g. run through a comb) so thatthey are oriented in a particular direction. The webs can be bondedtogether in any manner including e.g. hydroentangled, chemical bonded,needle punched or thermally bonded. In one embodiment, the nonwoven iscomprised of a blend of polypropylene and polyethylene fibers which areairlaid, carded and hydroentangled.

Any polymer film can be used. The polymer film can be selected from thegroup consisting of polyethylene, polypropylene, polyethylenecopolymers, polypropylene copolymers, and PET.

The first and second substrates can be nonwoven. The nonwoven can have abasis weight of less than 40 grams per square meter (gsm), less than 35gsm, or even less than about 30 gsm. The nonwoven can be extensible togreater than 100% in the cross-web direction.

Various post treatments, such as treatment with grooved rolls i.e.activation can be used to adjust the mechanical properties (e.g.extensibility) of the composite.

The hot melt adhesive can be applied to the first and or secondsubstrate using a variety of applicator methods including slot coating,non-contact coating, comb shim coating, spraying including, e.g., spiralspraying and random spraying, screen printing, foaming (e.g. usingchemical foaming agents or Nordson FoamMelt® Dispensing equipment),engraved roller, gravure roller, extrusion and meltblown.

The hot melt adhesive can be applied to one substrate.

Alternatively, the hot melt adhesive can be applied to the firstsubstrate and then contacted by the second substrate to form thecomposite. Pressure,tension and/or line speed can be used to aid informing the bonded composite. The composite can be formed within adisposable article manufacturing process. Alternatively, the compositeis formed prior to the disposable article manufacturing process.

In one embodiment, the elastic composite is formed by applying the hotmelt adhesive using a discontinuous application method. The hot meltadhesive application method can be selected from the group consisting ofcomb shim coating and spraying. Alternatively, any other method ofcoating could be used to give a discontinuous coating. In oneembodiment, the bonded elastic region alternates with an area free ofadhesive in a vertical stripe pattern throught the absorbent article.These vertical stripes can be more like a pin stripe. In one embodiment,the bonded elastic region is a 2 to about 10 mm wide stripe and the areafree of adhesive is a 0.5 to about 5 mm wide stripe, or even a 0.5 toabout 3 mm wide strip. Having areas free of adhesive, or using adiscontinuous method of hot melt adhesive application to form theelastic composite can be useful to give breathability to the composite.

Hot Melt Adhesive Composition

The hot melt adhesive can be a pressure sensitive adhesive (i.e. havesome tack at room temperature). The hot melt adhesive composition can belight in color and can have good thermal stability. In a cooled film,the hot melt adhesive can be clear i.e. translucent or alternatively thehot melt adhesive can be opaque. The hot melt adhesive can have aninitial Molten Gardner Color after manufacturing of less than about 3,or even less than about 2. Alternately, the hot melt adhesive can bepigmented to an opaque color such as e.g. pink, blue, white, gray, etc.

The hot melt adhesive composition has low viscosity at applicationtemperature. The viscosity can be no greater than about 15,000 cps ataround 177° C. (350° F.), no greater than about 10,000 cps at around177° C. (350° F.), no greater than about 7,500 cps at around 177° C.(350° F.), or even no greater than about 5,000 cps at 177° C. (350° F.).The hot melt adhesive composition gives a set after 50% hysterisis of nomore than about 20%, no more than about 12%, no more than about 10% oreven no more than about 8% when tested according to the 2-PeakHysterisis Test Method.

The hot melt adhesive composition provides good adhesion when testedaccording to the Peel Force Test Method. In some embodiments, the hotmelt adhesive has peel adhesion of greater than about 100 grams/inch,greater than about 200 grams/inch, or even greater than about 300grams/inch.

The hot melt adhesive composition includes one or more styrene blockcopolymers, a tackfying agent, and greater than about 15% by weight of aplasticizer.

The hot melt adhesive composition can have a viscosity curve with aViscosity Ratio (Viscosity @ 149° C. (300° F.) (cps)/Viscosity @ 177° C.(350° F.)) that is no greater than about 7.5, no greater than about 6,no greater than about 5, or even no greater than about 4. A lowviscosity ratio can indicate improved machining at high line speeds asthe hot melt adhesive gains viscosity more slowly as it cools.

The hot melt adhesive composition can include a tackifying agent with atleast some aromatic content and a naphthenic oil.

Styrene Block Copolymers

The hot melt adhesive includes one or more styrene block copolymers.

A styrene block copolymer includes an aromatic vinyl polymer block and aconjugated diene polymer block, a. hydrogenated conjugated diene polymerblock, or a combination thereof. The blocks can be arranged in a varietyof configurations including, e.g., linear, branched, radial, star block,and combinations thereof. The aromatic vinyl polymer block can bederived from a variety of aromatic vinyl compounds including, e.g.,styrene, alpha-methylstyrene, beta-methylstyrene, o-, m-,p-methylstyrene, t-butylstyrene, 2,4,6-trimethylstyrene,monofluorostyrene, difluorostyrene, monochlorostyrene, dichlorostyrene,methoxystyrene, 1,3-vinylnaphthalene, vinylanthracene, indene,acenaphthylene, and combinations thereof. The diene polymer block can bederived from a variety of diene-containing compounds including, e.g.,isoprene, butadiene, hexadiene, 2,3-dimethyl-1,3-butadiene,3-pentadiene, and hydrogenated versions thereof and combinationsthereof.

Useful styrene block copolymers include, e.g., diblock, triblock andmultiblock copolymers including, e.g., styrene-butadiene,styrene-butadiene-styrene, styrene-isoprene, styrene-isoprene-styrene,styrene-ethylene/butene, styrene-ethylene/butene-styrene,styrene-ethylene/propylene, styrene-ethylene/propylene-styrene,styrene-ethylene-ethylene/propylene-styrene, farnesene styrene andcombinations thereof and hydrogenated or functionatized versionsthereof.

The one or more styrene block copolymers have an average styrene contentof at least about 30%, at least about 35%, at least about 40%, or evenfrom about 35% to about 45% by weight.

As an example, if a hot melt composition comprises two styrene blockcopolymers A and B. Polymer A is present at 25 weight % with a styrenecontent of 35% and polymer B is present at 25 weight % with a styrenecontent of 45 weight %. The average styrene content of the one or morestyrene block copolymers is calculated in the following way: 0.5(35)+0.5 (45)=40 weight %.

The one or more styrene block copolymers have an average Melt Flow Rate(MFR) according to ASTM D 1238 (200° C./5 kg) in dg/min of no less thanabout 20 dg/min, no less than about 25 dg/min, or even no less thanabout 30 dg/min. The average MFR of the styrene block copolymers iscalculated in a similar manner as the average styrene content.

The hot melt adhesive can include at least one styrene block copolymerwith a styrene content of at least about 40% by weight.

The composition has a total styrene block copolymer content of greaterthan 40% by weight, greater than 45% by weight, from about 35% to about60% by weight, or even from about 40% to about 50% by weight.

The styrene block copolymers can be pure tri-block copolymers containingno di-block. Alternately, the styrene block copolymer can include aportion of di-block. The styrene block copolymer can include diblockcontent of greater than 30%.

Useful styrene block copolymers include VECTOR 6241 (Linear,styrene-butadiene-styrene, pure triblock copolymer, 43 wt % styrene, MFR(200° C./5 kg)=23 dg/min), VECTOR 8508 (Linear,styrene-butadiene-styrene, pure triblock copolymer, 29 wt % styrene, MFR(200° C./5 kg)=12 dg/min and VECTOR 4411 (Linear,styrene-isoprene-styrene, pure triblock copolymer, 44 wt % styrene, MFR(200° C./5 kg)=40 dg/min) all available from TSRC Dexco (Houston, Tex.)and GLOBALPRENE 3545 (Linear, styrene-butadiene-styrene block copolyer,63% diblock, 45 wt % styrene, MFR (190° C./5 kg)=55) available from LCYCHEMICAL CORP. (Taipei, Taiwan).

Tackifying Agent

The hot melt adhesive includes a tackifying agent. The tackifying agentcan be fluid or solid at room temperature. Suitable classes oftackifying agents include, e.g., aromatic, aliphatic and cycloaliphatichydrocarbon resins, mixed aromatic and aliphatic modified hydrocarbonresins, aromatic modified aliphatic hydrocarbon resins, and hydrogenatedversions thereof; terpenes, modified terpenes and hydrogenated versionsthereof; natural rosins, modified rosins, rosin esters, and hydrogenatedversions thereof; low molecular weight polylactic acid; and combinationsthereof. Examples of useful natural and modified rosins include gumrosin, wood rosin, tall oil rosin, distilled rosin, hydrogenated rosin,dimerized rosin and polymerized rosin. Examples of useful rosin estersinclude e.g., glycerol esters of pale wood rosin, glycerol esters ofhydrogenated rosin, glycerol esters of polymerized rosin,pentaerythritol esters of natural and modified rosins includingpentaerythritol esters of pale wood rosin, pentaerythritol esters ofhydrogenated rosin, pentaerythritol esters of tall oil rosin, andphenolic-modified pentaerythritol esters of rosin.

Useful tackifying agents are commercially available under a variety oftrade designations including, e.g., the ESCOREZ series of tradedesignations from Exxon Mobil Chemical Company (Houston, Tex.) includingESCOREZ 5400 (1% aromatic content), ESCOREZ 5600 (9.8% aromaticcontent), ESCOREZ 5690 (10% aromatic content), ESCOREZ 5615 (9.9%aromatic content), the EASTOTAC series of trade designations fromEastman Chemical (Kingsport, Tenn.) including EASTOTAC H-100R andEASTOTAC H-100L, and the WINGTACK series of trade designations from CrayValley HSC (Exton, Pa.) including WINGTACK 86, WINGTACK EXTRA, andWINGTACK 95 and the PICCOTAC and KRISTALEX series of trade designationsfrom Eastman Chemical Company (Kingsport, Tenn.) including, e.g.,PICCOTAC 8095 and KRISTALEX 3100.

The hot melt adhesive can be free from end block resin that has amelting point greater than about 110° C., greater than about 120° C., oreven greater than about 130° C.

The hot melt adhesive composition can include at least one tackifyingagent with aromatic content. The tackifying agent can have an aromaticcontent of greater than 5%, greater than 20%, greater than 50%, fromabout 5% to about 20% by weight, or even from about 7.5% to about 15% byweight. The aromatic content is measured by Nuclear Magnetic Resonance(NMR) spectroscopy.

The composition can include a tackifying agent with a melt point of lessthan 100° C., or even less than 95° C.

The hot melt adhesive composition can include at least about 20% byweight, at least about 25% by weight, from about 10% by weight to about50% by weight, from about 15% by weight to about 40% by weight, or evenfrom about 20% by weight to about 37% by weight tackifying agent.

Plasticizer

The hot melt adhesive composition includes a plasticizer. Suitableplasticizers include, e.g., napinhenic oils, paraffinic oils (e.g.,cycloparaffin oils), mineral oils, phthalate esters, adipate esters,olefin oligomers (e.g., oligomers of polypropylene, polybutene, andhydrogenated polyisoprene), polybutenes, polyisoprene, hydrogenatedpolyisoprene, polybutadiene, benzoate esters, animal oil, plant oils(e.g. castor oil, soybean oil (e.g. high oleic soy oil), derivatives ofoils, glycerol esters of fatty acids, polyesters, polyethers, lacticacid derivatives and combinations thereof.

Useful commercially available plasticizers include CALSOL 550 naphthenicoil from Calumet Specialty Products Partners, LP (Indianapolis, Ind.),KAYDOL OIL mineral oil from Sonneborn (Tarrytown N.Y.) PARAPOLpolybutene from Exxon Mobil Chemical Company (Houston, Tex.), OPPANOLpolyisobutylene from BASF (Ludwigsjhafen, Germany), KRYSTOL 550 mineraloil from Petrochem Carless Limited (Surrey, England), PURETOL 35 and 15both mineral oils from Petro Canada Lubricants Inc. (Mississauga,Ontario) and PLENISH from Pioneer Dupont.

The plasticizer can be a naphthenic oil. Alternately, the plasticizerincludes aromatic or naphthenic groups.

The plasticizer is present in the hot melt adhesive composition in anamount of at least about 15% by weight, at least about 18% by weight,from about 10% to about 30% by weight, or even from about 15% to about25% by weight.

Wax

The hot melt adhesive composition can include a wax. Useful classes ofwax include, e.g., paraffin waxes, microcrystalline waxes, high densitylow molecular weight polyethylene waxes, by-product polyethylene waxes,polypropylene waxes, Fischer-Tropsch waxes, oxidized Fischer-Tropschwaxes, functionalized waxes such as acid, anhydride, and hydroxymodified waxes, animal waxes, vegetable waxes (e.g. soy wax) andcombinations thereof. Useful waxes are solid at room temperature andpreferably have a Ring and Ball softening point of from 50° C. to 170°C. Useful waxes are commercially available from a variety of suppliersincluding EPOLENE N and C series of trade designations from WestlakeChemical Corporation (Houston, Tex.) including e.g. EPOLENE N-21 and theLICOCENE series of trade designations from Clariant International Ltd.(Muttenz, Switzerland) including e.g. TP LICOCENE PP 6102.

The hot melt adhesive composition can include no greater than about 8.0%by weight, no greater than about 5% by weight, from about 1% by weightto about 7.5 by weight, or even from about 1% to about 5% by weight wax.

Additional Components

The hot melt adhesive composition optionally includes additionalcomponents including but not limited to, e.g., foaming agents,stabilizers, antioxidants, additional polymers (e.g. olefin basedpolymers (e.g. propylene homopolymers, propylene copolymers, ethylenehomopolymers, ethylene copolymers, etc.), functionalized polymers suchas acid, anhydride, and hydroxy modified polymers), amorphous poly-alphaolefins), adhesion promoters, ultraviolet light stabilizers, corrosioninhibitors, odor absorbers/neutralizers, colorants (e.g., pigments (e.g.titanium dioxide, carbon black, and mixtures thereof) and dyes),fragrances, fillers (e.g. nano particles, calcium carbonate, clay, talc,fumed silica), surfactants, wetness indicators, superabsorbents,coextrusion coatings, processing aids and combinations thereof.

The hot melt adhesive can comprise from about 0.05 to about 2.0% byweight pigment, or even from about 0.05 to about 0.5% pigment.

Useful antioxidants include, e.g., pentaerythritoltetrakis[3,(3,5-di-tert-butyl-4-hydroxyphenyl)propionate],2,2′-methylene bis(4-methyl-6-tert-butylphenol), phosphites including,e.g., tris-(p-nonylphenyl)-phosphite (TNPP) andbis(2,4-di-tert-butylphenyl)4,4′-diphenylene-diphosphonite,di-stearyl-3,3′-thiodipropionate (DSTDP), and combinations thereof.Useful antioxidants are commercially available under a variety of tradedesignations including, e.g., the IRGANOX series of trade designationsincluding, e.g., IRGANOX 1010, IRGANOX 565, and IRGANOX 1076 hinderedphenolic antioxidants and IRGAFOS 168 phosphite antioxidant, all ofwhich are available from BASF Corporation (Florham Park, N.J.), andETHYL 702 4,4′-methylene bis(2,6-di-tert-butylphenol). When present, thehot melt adhesive composition preferably includes from about 0.1% byweight to about 2% weight antioxidant.

Disposable Article

The hot melt adhesive compositions and elastic composites of thisinvention can be incorporated into any suitable article includingpersonal care garments, medical garments and industrial worker garments.

The elastic composite of this invention is useful in a variety ofapplications and constructions to improve comfort and fit includinge.g., disposable absorbent articles including, e.g., diapers, trainingpants, swim wear, absorbent underpants, adult incontinence products,sanitary napkins, medical dressings (e.g., wound care products andbandages), surgical pads, medical gowns, caps, gloves, drapes, facemasks, laboratory coats, coveralls, meat-packing products, andcomponents of absorbent articles including, e.g., an absorbent clement,absorbent cores, impermeable layers (e.g., backsheets), tissue (e.g.,wrapping tissue), acquisition layers and woven and nonwoven web layers(e.g., top sheets, absorbent tissue).

The elastic composite of this invention is useful for elasticizing manyareas of disposable articles including leg cuffs, waist portions, bellybands, side panels and fastening tabs/ears. The elastic composite ofthis invention can further be use to elasticize any portion. of thedisposable article, one or more portions of the disposable article, oreven the entire disposable article.

EXAMPLES

Composition amounts in tables are all in weight %.

Test Procedures

Test procedures used in the examples and throughout the specification,unless stated otherwise, include the following.

Viscosity Test Method

Viscosity is determined in accordance with ASTM D-3236 entitled,“Standard Test Method for Apparent viscosity of Adhesives and CoatingMaterials,” (Oct. 31, 1988), using a Brookfield Thermoset viscometerModel RVDV 2 and a number 27 spindle. The results are reported incentipoise (cps).

Molten Gardner Color

The hot melt adhesive is tested (in the molten state) to determineMolten Gardner Color by comparing the color of the sample against theGardner Color Standards as set forth in ASTM D-1544. The comparison ismade using a Gardner Delta Comparator equipped with an Illuminatoravailable from Pacific Scientific (Bethesda, Md.).

Test Lamination Preparation

Test laminations were prepared by continuous slot coating the elastichot melt adhesive composition between two nonwoven* substrates at anapplication temperature of 177° C. (350° F.), a nip pressure of 10.5Newtons/centimeter (N/cms) (6 pounds per linear inch (PLI)), and a runspeed of at least 6.1 meters/min (m/min) (20 feet/min). Laminations wereprepared with an adhesive coat weight of 100 grams per square meter(gsm) and the width of the adhesive was at least 7.6 cms (3 inches). Asufficient amount of laminate was prepared such that at least 1.5 m (60inches) of representative lamination was collected for testing. *Thenonwoven used is carded, hydroentangled and comprises 50/50 (PET/PP). Ithas a basis weight of 29 g/m², a cross direction tensile strength of 93grams/cm² (600 grams/in²), a CD elongation at break=217% WSP Method110.4, and an elongation ratio (CD/MD)=4.3.

Peel Force Test Method

Test laminates were prepared by coating adhesive between two substratesaccording to the Test Lamination Preparation method above. Peel force isdetermined using ASTM D1876-01 entitled; “Test Method for DeterminingPeel Resistance of Adhesive (T-Peel Test Method),” with the exceptionthat the test is run at a rate of 30.5 cms per minute (12 inches perminute), instead of 25.4 cms per minute (10 in per minute), over aperiod of 10 seconds, and 7 replicates are run instead of the 10specified in ASTM D1876. The samples are run on on INSTRON type-testinstrument. The test samples are 2.54 cms (1 inch) in width and at least10.16 cms (4 inches) in length. The average peel force over 10 secondsof peeling is recorded, and the results are reported in grams. Theinitial peel force is measured at least 24 hours after the laminate isprepared.

2-Peak Hysteresis Test Method

Test laminates were prepared by coating hot melt adhesive between twosubstrates according to the Test Lamination Preparation method above.Test samples are prepared by cutting the laminates in cross-webdirection, with 1 inch in width and at least 3 inches in length. Thetest is conducted at least 24 hours after the non-woven laminate isprepared.

The strips prepared are extended to a certain strain (e.g. 50%, 100%,150% or 200%) and then retracted to their original dimension.Subsequently the specimen goes through a second extension-retractioncycle with the same deformation. The cross head speed is set to 50.8 cmsper minute (20 inches per minute). There is no holding time betweenextension and retraction. The samples are run on an INSTRON type-testinstrument with at least 3 replicates. The permanent set after eachcycle is determined by the tensile strain on the retraction curve whenthe tensile stress reduces to 5 gram force. The peak loadlstress atmaximum deformation, and percent energy loss between each cycles arealso recorded.

Rheological Creep and Recovery

Rheological Creep and Recovery was run on a Texas Instruments AR-G2rheometer using parallel plate geometry with a 8 mm plate. The test wasrun isothermally at 38° C. with a gap of 300 um.

Once equilibrated at 38° C., a pressure of 26,800 Pa was applied. Thesample was held at this pressure for 20 minutes (creep portion of test).The pressure was then released to 0 Pa for 20 minutes (recovery portionof test).

The strain was measured. Values at specified intervals are reported inthe table.

TABLE ONE Comparative 1 and 2 are compositions outside of the inventiveranges (Comparative 1 has less than 15% plasticizer and Comparative 2has a styrene block copolymer with an average MFR of 12 dg/Min. Bothhave a viscosity at 350° F. of greater than 15,000 cps). Both would beexpected not to apply well on a high speed production line. Comparative1 Comparative 2 VECTOR 8508 40 45 (Avg. MFR (200° C./5 kg) = 12) ESCOREZ5615 49.5 29.5 CALSOL 550 10 25 IRGANOX 1010 0.5 0.5 Viscosity @ 350° F.(cps) 43,400 30,870

TABLE TWO Ex. 1 Ex. 2 Ex. 3 Ex. 4 Ex. 5 Ex. 6 VECTOR 6241 20 VECTOR 441146 46 46 42.5 42.5 26 ESCOREZ 5490 32 ESCOREZ 5400 33.5 ESCOREZ 569033.5 33.5 32 31.5 PURETOL 35 20 20 25 CALSOL 550 20 25 22 PLENISH IRG1010 0.5 0.5 0.5 0.5 0.5 0.5 Viscosity (cps) @149° C. 204,500 68,00038,800 77,000 18,250 33,500 (300° F.) @177° C. 14,050 9,700 8,020 6,9504,210 8,940 (350° F.) Viscosity 14.56 7.01 4.83 11.10 4.34 3.75 Ratio@149° C./ @177° C. Rheo. Creep Strain @ .078 .067 0.01 sec Strain @ .232.169 600 sec Strain @ .246 .192 1200 sec Rheo. Recovery Strain @ .246.192 1200 sec Strain @ .05 .041 1800 seconds Strain @ .043 .033 2400 secEx. 7 Ex. 8 Ex. 9 Ex. 10 Ex. 11 VECTOR 6241 20 VECTOR 4411 26 50 50 3535 ESCOREZ 5490 29.5 29.5 38.5 ESCOREZ 5400 ESCOREZ 5690 31.5 29.5 38.5PURETOL 35 20 26 CALSOL 550 20 26 PLENISH 22 IRG 1010 0.5 0.5 0.5 0.50.5 Viscosity (cps) @149° C. 28,100 279,600 74,800 18400 6000 (300° F.)@177° C. 7,750 30,150 12,550 2545 2065 (350° F.) Viscosity 3.63 9.27 6.07.23 2.91 Ratio @149° C./ @177° C. Rheo. Creep Strain @ .052 .084 .0780.01 sec Strain @ .162 .457 .377 600 sec Strain @ .189 .488 .424 1200sec Rheo. Recovery Strain @ .189 .488 .424 1200 sec Strain @ .048 .106.104 1800 seconds Strain @ .039 .094 .087 2400 sec

TABLE THREE Ex. 12 Ex. 13 Ex. 6 Ex. 14 Ex. 15 Ex. 16 Ex. 17 VECTOR 850820 15 VECTOR 4411 26 31 26 26 46.5 VECTOR 6241 20 20 30 46.5 GLOBALPRENE3545 15 Avg. Styrene 37.5 39.1 43.6 43.6 43.7 44 43 Content of SBC Avg.MFR 27.8 30.9 32.6 32.6 >33 40 23 (200° C./5 kg) ESCOREZ 5690 31.5 31.531.5 33.5 29.75 29.75 ESCOREZ 5615 34.5 CALSOL 550 22 22 22 20 20 23.2523.25 IRGANOX 1010 0.5 0.5 0.5 0.5 0.5 0.5 0.5

TABLE FOUR Ex. 12 Ex. 13 Ex. 6 Ex. 14 Ex. 15 Ex. 16 Ex. 17 Viscosity(cps) @149° C.(300° F.) 47,000 48,590 33,500 33,000 33,800 35,150 37,800@163° C.(325° F.) 23,125 21,570 16,290 16,150 17,750 14,250 18,850 @177°C.(350° F.) 12,700 12,800 8,940 9,250 11,050 7,050 12,050 ViscosityRatio 3.70 3.80 3.75 3.56 3.06 4.99 3.11 @149° C./177° C. 2-PeakHysteresis Testing 50% hysteresis Set 1^(st) cycle (%) 6 6 6 8 9 6 5 Set2^(nd) cycle (%) 7 6 7 10 10 7 6 Energy loss (%) 31.1 31.1 35.1 37.037.9 35.1 34.5 100% hysteresis Set 1^(st) cycle (%) 15 14 15 21 23 16 14Set 2^(nd) cycle (%) 17 17 17 23 26 18 16 Energy loss (%) 43.0 44.2 46.748.7 51.2 46.9 45.6 150% hysteresis Set 1^(st) cycle (%) 24 24 27 37 4126 23 Set 2^(nd) cycle (%) 27 27 30 40 45 28 27 Energy loss (%) 54.355.1 55.2 59.8 61.6 56.2 54.4 Adhesion Average peel 278 238 437 256 85268 272 (gram force)

What is claimed is:
 1. An elastic composite comprising: a first andsecond substrate; and a hot melt adhesive composition between the firstand second substrates thereby permanently bonding the first and secondsubstrates to each other and providing elasticity in the bonded area,said hot melt adhesive composition comprising: about 35% by weight toabout 60% by weight of one or more styrene block copolymers wherein theone or more styrene block copolymers has an average styrene content ofat least about 30% by weight and an average MFR (200° C./5 kg) of noless than about 20, greater than about 15% of a plasticizer and, atackifying agent; wherein the hot melt adhesive composition has aviscosity of less than about 15,000 cps at 177° C. (350° F.).
 2. Theelastic composite of claim 1 wherein the hot melt adhesive compositionhas a viscosity of less than about 10,000 cps at 177° C. (350° F.). 3.The elastic composite of claim 1 wherein the one or more styrene blockcopolymers have an average styrene content of at least about 35% byweight.
 4. The elastic composite of claim 1 wherein the hot meltadhesive composition comprises from about 25% by weight to about 40% byweight tackifying agent.
 5. The elastic composite of claim 1 wherein thehot melt adhesive composition comprises at least one tackifying agentwith a melt point of less than 100° C.
 6. The elastic composite of claim1 wherein the first and second substrate are nonwoven.
 7. The elasticcomposite of claim 6 wherein the nonwoven is airlaid, carded andhydroentangled.
 8. The elastic composite of claim 6 wherein the nonwovenis extensible to greater than 100% in the cross web direction.
 9. Theelastic composite of claim 1 wherein the hot melt adhesive is applied tothe substrate using an applicator method selected from the groupconsisting of slot and non contact coating.
 10. The elastic composite ofclaim 1 wherein the hot melt adhesive is applied to the substrate usingan applicator method selected from the group consisting of screenprinting, spraying, comb shim slot and gravure roll.
 11. A disposablearticle comprising the elastic composite of claim
 1. 12. The disposablearticle of claim 11 wherein the elastic composite is used in anapplication selected from the group consisting of ear, waist band, bellyband and side panel.
 13. The disposable article of claim 11 selectedfrom the group consisting of diaper, adult incontenence product,feminine hygiene product and medical bandage.
 14. A hot melt adhesivecomposition that can be used to create a bonded, elasticized region,comprising: from about 35% to about 60% by weight of one or more styreneblock copolymers wherein the one or more styrene block copolymers has anaverage styrene content of at least about 35% and an average MFR (200°C./5 kg) of no less than about 20, greater than about 15% plasticizingoil and, a tackifying agent wherein the adhesive composition has aviscosity of less than about 15,000 cps at 177° C. (350° F.).
 15. Thehot melt adhesive of claim 14 wherein the hot melt adhesive compositionhas a Viscosity Ratio (Viscosity @ 149° C. (300° F.) (cps)/Viscosity @177° C. (350° F.) of no greater than about
 5. 16. The hot melt adhesivecomposition of claim 14 wherein the tackifying agent is a hydrocarbonresin with about 5% to about 20% by weight of aromatic content and theplasticizing oil is a naphthenic oil.
 17. A hot melt adhesivecomposition that can be used to create a bonded, elasticized region,comprising: from about 40% to about 50% by weight of one or more styreneblock copolymers wherein the one or more styrene block copolymers has anaverage styrene content of at least about 35% and an average MFR (200°C./5 kg) of no less than about 20, from about 15% to about 30% of anaphthenic plasticizing oil and, from about 30% to about 40% by weightof an aromatic modified hydrocarbon resin; wherein the adhesivecomposition has a viscosity of less than about 15,000 cps at 350° F. 18.The hot melt adhesive of claim 17 wherein at least one of the styreneblock copolymers has a diblock content of greater than about 30% byweight.
 19. The hot melt adhesive of claim 17 wherein the averagestyrene content of the one or more styrene block copolymers is at leastabout 40% by weight.
 20. An elastic composite comprising: a nonwovensubstrate, and the hot melt adhesive composition of claim 14 bonded tothe substrate; wherein the hot melt adhesive provides elasticity to thebonded area.